Vibratory granulate compacting apparatus for block manufacture

ABSTRACT

An essentially tubular shell has movable tops and bottoms, which are subjected to vibratory impacts in non-cyclically recurring pulses; top or bottom may be subjected to a constant pressure, or both may be subjected to impacts which are synchronized and opposite each other. The impact pulses are controllable both as to frequency (which may be zero), amplitude and wave shape, the impulses being preferably controlled from an electrical programming source which controls application of pressure fluid to the top and bottom.

States Patent 1 Blaser VllBRATORY' GRANULATE COMPACTING APPARATUS FORBLOCK MANUFACTURE [75] Inventor: Harry Blaser, Oensingen,

Switzerland [73] Assignee: Von Roll A.G., Gerlafingen,

Switzerland [22] Filed: Oct. 13, 1971 [21] Appl. No.: 188,715

[30] Foreign Application Priority Data Oct. 22, 1970 Switzerland15636/70 Nov. 9, 1970 Switzerland 16671/70 [52] U.S. Cl 425/432,425/167, 425/352 [51] Int. CL... B28b 3/08 [58] Field of Search 425/352,355, 167, 425/432 [56] References Cited UNITED STATES PATENTS 3,689,1869/1972 Winter 425/352 Oct. 23, 1973 3,050,809 8/1962 Kupka 425/3523,616,495 11/1971 Lemelson.... 425/167 X 3,013,321 12/1961 McElroy425/167 X 2,348,197 5/1944 Ernst et al. 425/352 X Primary Examiner-J.Spencer Overholser Assistant Examiner-B. D. Tobor Attorney-Flynn &Frishauf [57] ABSTRACT An essentially tubular shell has movable tops andbottoms, which are subjected to vibratory impacts in noncyclicallyrecurring pulses; top or bottom may be subjected to a constant pressure,or both may be subjected to impacts which are synchronized and oppositeeach other. The impact pulses are controllable both as to frequency(which may be zero), amplitude and wave shape, the impulses beingpreferably controlled from an electrical programming source whichcontrols application of pressure fluid to the top and bottom.

19 Claims, 3 Drawing Figures PATENTED URI 23 I975 SHEET 2 OF 3 PATENTEU0U 23 I975 SHEET 3 BF 3 Fig 2/;

Tan k v Fad/a for VIBRATORY GRANULATE COMPACTHNG APPARATUS FOR BLOCKMANUFACTURE The present invention relates to a vibratory compactingapparatus particularly to manufacture blocks from granulates, such asblock anodes, in which granulates are placed into a shell and subjectedto vibration treatment, in which the granulates are compacted.

The manufacture of blocks from granulates by means of vibratorytreatment is known. It has been proposed to utilize resilientlysupported tables, or the like, on which the form in which the granulatesare filled, is mounted. Such a vibratory table usually has a pair ofrotating, unbalanced weights applied thereto. The unbalanced weights maybe so arranged that their horizontal components cancel each other. Smallvibratory tables of this type can utilize an electric motor which ismounted directly on the vibratory table in order to drive the rotatingunbalanced weights. Large vibratory tables, however, require remotelylocated electric motors. The drive to the unbalanced weights then isover shafts with universal joints therein, or otherwise flexible shafts.Rotation of the unbalanced weights results in an essentially harmonicoscillation of the vibratory table, the granulate within the form beingvibrated into one compact block. The compaction of the granulate uponvibration depends on the frequency and amplitude of vibrations.

Remotely located drives, transmitting power over shafts having universaljoints, or the like therein are practically always used for vibrationtables of high power. Such an arrangementv requires a substantial amountof space, since the shafts and the universal joints require aconsiderable length in order to compensate for the motion of thevibration table. The frequency can be changed by changing the speed ofrotation, and amplitude of vibration can be changed within small limits;the type of vibration is, however, always cyclically recurring, due tothe drive from a constant speed, or essentially constant speed motor.

It has been found that vibration of granulates to provide compaction isnot as effective as non-harmonic, that is non-cyclically recurringvibrations, such as pulses, impacts and abrupt blows, presenting awelldefined maximum of energy for a short period of time, that is, whenlooked at in an oscillograph representation, presenting sharplydefinedpeaked pulses.

- It is'an object of the present invention to provide a compactingapparatus to compact granulates into blocks, which is compact, utilizesbut small space for the energy source,and which is capable of providingenergy for compaction which is non-cyclically recurring. By non-cyclicalrecurrance rate, as referred to in the present specification, a motionis meant which is nonharmonic in the sense of showing cyclicallyrecurring oscillations.

Subject Matter of the Present Invention Briefly, a shell is providedhaving movable top and bottom parts, which are connected to a powertransfer device such as a pressure fluid operated piston-cylinderarrangement. The granulate to be compacted is placed within the shell,and energy pulses are applied to at least one of the top, or bottomparts in non-cylically recurring pulses. One of the parts may besubjected to a constant compaction pressure, while the other issubjected to impacts, so that blows will be transmitted to the granulateto be compacted; or, both the top and bottom cover parts may be operatedin synchronism, and in counter-acting directions so that compactingblows are delivered against the granulate within the shell, from boththe top and the bottom.

In accordance with a feature of the invention, the blows are controlledfrom a programming source, which may be electrical, which provides acontrol for a transducer applying pressure fluid to the cylinderpistonarrangement. In addition to the cylinder-piston arrangementstransmitting the blows, a steady compacting pressure may be exerted, forexample by mounting one of the cylinder-piston arrangements transmittingthe blow on a housing portion which is subjected to pressure, forexample hydraulic pressure.

In accordance with a feature of the invention, both the amplitude, waveform and frequency of the compacting impulses is changeable; thefrequency of compacting pressure applied to one of the cylinder-pistonarrangements may be zero, that is, provide a constant essentiallyunvarying compacting pressure.

By providing pressure fluid operated cylinderpistons, directly actingover movable parts of the container'within which the granulate isplaced, space for the apparatus is reduced and the source of energy maybe located anywhere, connected to the apparatus itself merely by a fluidpressure line, such as a hydraulic pressure fluid line. Control ofadmission of the hydraulic pressure fluid is simple and can be carriedout by means of electromagnetically operated valves, in accordance withan established program.

The invention will be described by way of example with reference to theaccompanying drawings, wherein:

FIG. 1 is a highly schematic illustration of the apparatus to makeblocks, and generally illustrating the application of the invention;

FIG. 2a is a schematic longitudinal sectional view through an apparatusto compact granulates; and

FIG. 2b is a schematic diagram illustrating control connections, andprogramming control for the apparatus of FIG. 2a.

Referring to FIG. 1: A press, or similar suitable arrangement has amovable bottom 201, slidable within a shell 202. Granulate, generallyindicated at 203 is placed into the shell. The bottom 201 is connectedto a stand 204 which bears against a base 205 in any suitable manner,and not illustrated in FIG. 1. The bearing connection between base 205and bottom 204 can be fixed, or can be resilient, that is, can be overinterposed springs (not shown). An impacting apparatus 206, providingupward motion to the bottom 201 is located within base 204. Since theimpacts can be recurring the apparatus will be referred to as a vibratoralthough it is to be understood that the recurrence rate of vibrationsapplied to the bottom 201 on which the granulate 203 is located isnon-cyclical. The vibrator,

or impacting device 206 has an impacting transducer operable in only asingle directionmamely axially with respect to the shell 202, andtransmitting blows or impacts against the granulate. In FIG. 1, thedirection of impacts is vertical. This permits utilization of a singlevibrator, which has advantages based on economics and spaceavailability. The vibrator apparatus 206 provides blows and impactswhich are non-harmonic, that is, non-cyclically recurring.

An energy source 207 which may,- for example, be a source of compressedair, hydraulic fluid, or electrical energy, provides energy over line208 to a control device 209. The controlled energy is then transmittedover line 211 to the vibrator. The interconnection of lines 208, 211,and the placement of the control apparatus 209 is variable in accordancewith available space, and operating requirements.

Control apparatus 209, providing controlled application of energy overline 211 to the impacting apparatus 206 is itself controllable by meansof a controller 210 which may be manually operated, or electrically, forexample by means of a programming source.

The vibrator itself is a cylinder-piston arrangement having massesmovable relative with respect to each other, as controlled by the energyover lines 208, 211. One of these masses can be fixed with the bottom201, or can be elastically secured thereto.

The granulate can be vibrated entirely from the bottom. It is, however,preferred and increases the compacting effect when the top of thegranulate is likewise loaded. A top cover 212, within a cylinder-pistondevice 213 is provided, which can be lowered against the top of thegranulate. The cylinder-piston arrangement 213 provides a steadyconstant pressure against the granulate or, as will appear hereafter,can likewise be controlled to provide impacts or blows against thegranulate, preferably in synchronism, and in opposite direction with theblows provided by device 206 and connected to the bottom. The topcompacting arrangement is not strictly necessary, however, since thenoncyclically recurring, .that is the non-harmonic vibrationstransmitted from the device 206 already provide for substantialcompaction.

A specific example of the apparatus is shown in FIG. 2a, wherein thedevice 1 is shown as a whole. A base 2 has a machine frame 4 supportedthereon by means of springs 3. A housing 5 is located within frame 4,the housing including a shell 6, a top cover 7 and a bottom cover 8, theparts 6, 7 and 8 being sealed with respect to each other by seals 9, 10.

The interior of shell 5 has a top part 12 and a bottom part 13, partsl2, 13 being longitudinally guided by rods 14, 15, in the direction ofthe longitudinal axis of the housing 5.

Top part 12, which forms a pressure piston, has a piston rod 16 securedthereto; slidable within a pistoncylinder arrangement 17. Thecylinder-piston arrangement 17 includes a cylinder portion 18 withinwhich a cylinder 20 and a cylinder housing 21 are located. The cylinderhousing 21 also carries control equipment to be described below.Cylinder housing 21 is secured to the inner wall of the upper cover 7.

A cylinder-piston arrangement which may be identical, or similar to theone just described, is located at the bottom of the shell, beneath abottom part 13 forming a counteracting piston. Bottom part 13 has apiston rod 23 connected to the bottom part 13. It includes a cylinderportion 24 and a piston 25. Cylinder portion 24 has a cylinder 26 and acylinder housing 27, the cylinder housing 27 carrying control equipmentto control the piston drive 22, and which will be described below.Cylinder housing 27 is not connected to the bottom shell, as the topcylinder housing, but rather is com nected to a table 29 of anadditional cylinder-piston drive 30. The cylinder 32 of the additionalcylinderpiston drive is secured to the lower portion 8, closing off theshell. Pressure lines 31 lead to the additional cylinder 32.

A bracket 35 extends from frame 4, and supports a further cylinderpiston arrangement 36. The piston rod 37 is pivotally connected to alink 38 which is secured to a shaft 39, joumalled on machine frame 4. Anarm 40 is secured to the top cover 7 for the shell and is likewiseconnected to shaft 39. Upon application of differential pressure tolines 41, 43, into cylinder-piston drive 36, the piston rod 37 islowered, thus swinging shaft 39 and permitting removal of the top cover7 and all mechanism enclosed therein from the shell 6, so that granulate44 can be introduced within the shell 6, for compaction therein.

Line connections 45, 47 are introduced above the top piston 12, andbelow the bottom piston 13, and in the top and bottom regions of theapparatus. Connections 45, 47 are connectable with lines 48, 49 whichcan be connected to a suction apparatus 50 of any suitable form.

The compactor 1 is operated by hydraulic pressure. The hydraulicpressure, that is, the pressure pulses, are controlled from aprogramming source 60 (FIG. 2b), which is programmed to provide outputsignals which can vary as schematically indicated by boxes 61, 62, 63,64. The programmer thus provides an output signal in which the feed ofprojection of any one of the pistons 12, 13 can be controlled (see boxofdiagram 61). Likewise, amplitude A (diagram 62); frequency, orduration of impact (diagram 63) and wave shape (diagram 64) arecontrollable. The signal provided from programmer 60 represents acommand signal. It is applied over two parallel channels 65, 66 tocomparator 67, 68, where the command signal is compared with actualposition signals applied over lines 69, 70 and 71, 72, respectively. Theerror signal is applied over line 73, 74 to amplifier 75, 76, suppliedfrom a power source 77, the amplified signal being conducted over lines78, 79 to transducers and amplifiers 80, 81 (FIG. 2a). Thetransducer-amplifiers 80, 81 may be electro-hydraulic servo valves whichapply pressure fluid, such as hydraulic pressure fluid to thepiston-cylinder arrangement 17, 22, respectively.

The valve may also control compressed air, or other pressure fluids;rather than utilizing valves, the control signals can be applied tomagnetically operated impacting devices, over mechanical or solid staterelays.

The transducers 80, 81 as shown in FIG. 2a are supplied over lines 82,83 with hydraulic fluid under high pressure; the fluid at low pressureis taken over lines 84, 85 back to a reservoir or sump 87 (FIG. 2b),preferably over a radiator 86 to cool the fluid, to be then picked up bya pump 88, driven by a motor 89, and supplied over a filter 90 to apressure reservoir 91. The pressure at pressure reservoir 91 iscontrolled by means of a pressure regulating valve 92.

Transducer-amplifiers 80, 81 are connected over lines 93, 94, 95, 96with the two piston-cylinder arrangements 17, 22 respectively. Positiontransducers 97, 98 for the transducer amplifiers 80, 81, and positiontransducers 99, 100 for piston rods 16, 23 provide feedback signalswhich are conducted over lines 69, 70, 71, 72 to the comparators 67, 68(FIG. 2b), to be there compared with the command signal from theprogrammer 60.

A completely closed control loop is provided. The arrangement need not,however, have the closed control loop, in which measured positionsignals are compared with command signals, and the motion is controlledby an error signal. Other arrangements are possible. In the particularexample shown, the two pistoncylinder drives 17, 22 provide the sameimpacts to the granulate 44 within shell 5, that is, bothpiston-cylinder drives are controlled by a single programming source 60,acting in opposition from each other, so that pistons l2, 13 will havethe same motion, directed towards each other, in synchronism. Differentprogramming arrangements can be used, that is, each one of the pistons12, 13 may be controlled by its own programmer, or a single programmercan be used in a time-sharing arrangement. The feeback circuit describedin detail is not necessary, but it provides for greater accuracy; directconnection of control signals from a programmer 60 to the respectivepistons 12,13 can likewise be used.

The pressure medium applied to the cylinder-piston combinations 17, 22is either hydraulic, or pneumatic. Indicators 102, 104 (FIG. 2b) can beincluded in the feedback circuit 70, 72 which indicates the actualposition of the pistons 12, 13 confining the granulate within the shell.Other indicators, or controllers and recorders can be connected as iswell known in the art.

In the described example, the position of the pistons l2, 13 is used asa feedback signal. It is also possible to measure pressure being exertedby the pistons and compare the exerted pressure with a programmingsource providing pressure impacting signals.

The apparatus of the present invention can be used in accordance withvarious combinations of feed, steady pressure, impacts, and impactssuperimposed on steady pressure or slowly varying pressure. At pressurevariation with zero frequency, that is, at even or only very slowlychanging pressure feed, the granulate is compacted by the pressure ofthe two piston-cylinder arrangements 17, 22 compressing the granulate.Superimposed non-cyclically recurring impacts provide additional energyfor effective compaction of the granulate.

Various changes and modifications may be made within the inventiveconcept.

I claim:

1. Vibratory granulate compacting apparatus for the manufacture ofblocks comprising a housing;

a multi-part container having a bottom part, a top part and a shell partlocated between the bottom and top part and having a central axis, thegranular material being placed within the container for compaction;

a piston means connected to at least one of the parts to move theconnected part in axial direction for compaction of material locatedwithin the container by steady-state pressure and, selectively,vibratory motion;

fluid energy means connected to said piston means and moving said pistonmeans to provide compacting pressure and vibratory impacts in axialdirection, the energy having parameters including amplitude, frequency,wave shape;

a fluid energy source;

electrical signal controlled fluid control means controlling applicationof fluid energy from said source to said energy means; and

programmed electrical control means generating signals representative ofat least one of said parameters, connected to and controlling saidsignalcontrolled fluid control means to apply said fluid energycontrolled by one of said parameters.

hydraulic pressure fluid.

3. Apparatus according to claim 1, comprising a pair of energy means,one each connected to the bottom and top part of the multi-partcontainer, respectively;

and the piston means comprises a top and a bottom piston, respectivelyconnected to the top and bottom part.

4. Apparatus according to claim 3, wherein one of the energy means iscontrollable to provide steady compacting pressure, whereby thefrequency of compaction is zero;

and the other energy means is controllable to provide impacts atnon-cyclically recurring intervals to prevent harmonic oscillations frombeing established.

5. Apparatus according to claim 3, wherein the energy means connected toboth the top and bottom parts are controllable to provide, each,counter-acting synchronized impacts directed towards each other.

6. Apparatus according to claim 3, wherein the energy means comprises acylinder for the piston to form a piston-cylinder combination;

one of the cylinder parts of one piston-cylinder combination is fixedlyconnected to the housing; the pistons of both said piston-cylindercombinations being connected to the bottom and top parts respectively;and the other cylinder part is slidably secured in the housing.

7. Apparatus according to claim 6, including an additionalcylinder-piston combination supporting the other cylinder part.

8. Apparatus according to claim 7, wherein the housing closes the topand bottom parts and has a separable, removable top and bottom cover;

one of the cylinders being secured to the removable top cover, and theadditional cylinder-piston combination being secured to the bottomcover.

9. Apparatus according to claim 8, wherein at least one of the top andbottom covers is removable from the housing as an entirety including therespectively connected piston-cylinder combination.

10. Apparatus according to claim 1, wherein the means applying energy tothe parts, and the means controlling the frequency and amplitudeparameter of application of energy comprises a source of controlsignals;

transducer and amplifier means controlled by the control signal;

and means interconnecting the transducer means and the amplifier meanswith the energy means.

11. Apparatus according to claim 10, wherein the control signals derivedfrom the source provide signals of opposite polarity;

and a pair of energy means are provided acting in opposite axialdirections, one energy means each being controllable by one of thesignals.

12. Apparatus according to claim 1, including resilient means supportingthe housing.

13. Apparatus according to claim 1, wherein the housing is sealed;

and suction outlet means are provided both at the upper and lowerportions of the housing. I

14. Compaction apparatus comprising a generally tubular shell (6);

top piston and bottom pistons (12, 13) slidable in said shell, thematerial to be compacted being placed in the shell between the pistons;

top and bottom housing covers (7, 8) secured to the shell (6) andenclosing said top and bottom pistons, respectively;

hydraulic power means (17, 22) controlling movement of the pistons intothe shell to compact granulate therein; an electro-hydraulic and programmeans (60) connected to said control loop and controlling the powermeans (17, 22) applying hydraulic pressure by each said pistons (12, 13)with respect to at least one of: amplitude; frequency; and wave shape ofapplied power to provide for compacting and retracting movement of thepistons and vibratory impacts thereof to be transmitted from the pistonsto the material within the shell, as controlled by said program means(60).

15. Apparatus according to claim 14, wherein the program meanscontrolling the power means comprises a random signal generatorproviding non-cyclically recurring power control signals.

control loop (60,65-85,

16. Apparatus according to claim 14, wherein the program meanscontrolling the power means comprises a signal generator;

and the electrohydraulic control loop comprises transducer meansconnected to the power means to transduce the signals from the signalgenerator to compression strokes by said top, and bottom piston,respectively.

17. Apparatus according to claim 16, wherein the signal controllingapplication of power to one of the pistons is a slowly, or unvaryingcompression signal and the signal controlling the other piston is apulse-type signal providing impact, or blow-type excursions of the otherpiston at non-cyclically recurring rates.

18. Apparatus according to claim 15, wherein the signal from the signalgenerator controlling application of power controls both said pistons tomove synchronously in opposition towards each other to providecounter-acting compression impacts against the material in the shell.

19. Apparatus according to claim 2, comprising hydraulic connectionmeans connecting the fluid energy source and the cylinder-pistoncombination, the electrical signal controlled fluid control means beinginterposed in the connection means and being located on the cylinder ofthe piston-cylinder combination.

1. Vibratory granulate compacting apparatus for the manufacture ofblocks comprising a housing; a multi-part container having a bottompart, a top part and a shell part located between the bottom and toppart and having a central axis, the granular material being placedwithin the container for compaction; a piston means connected to atleast one of the parts to move the connected part in axial direction forcompaction of material located within the container by steady-statepressure and, selectively, vibratory motion; fluid energy meansconnected to said piston means and moving said piston means to providecompacting pressure and vibratory impacts in axial direction, the energyhaving parameters including amplitude, frequency, wave shape; a fluidenergy source; electrical signal controlled fluid control meanscontrolling application of fluid energy from said source to said energymeans; and programmed electrical control means generating signalsrepresentative of at least one of said parameters, connected to andcontrolling said signal-controlled fluid control means to apply saidfluid energy controlled by one of said parameters.
 2. Apparatusaccording to claim 1, wherein the energy means comprises a cylinder forthe piston to form a piston-cylinder combination, the fluid energy beinghydraulic pressure fluid.
 3. Apparatus according to claim 1, comprisinga pair of energy means, one each connected to the bottom and top part ofthe multi-part container, respectively; and the piston means comprises atop and a bottom piston, respectively connected to the top and bottompart.
 4. Apparatus according to claim 3, wherein one of the energy meansis controllable to provide steady compacting pressure, whereby thefrequency of compaction is zero; and the other energy means iscontrollable to provide impacts at non-cyclically recurring intervals toprevent harmonic oscillations from being established.
 5. Apparatusaccording to claim 3, wherein the energy means connected to both the topand bottom parts are controllable to provide, each, counter-actingsynchronized impacts directed towards each other.
 6. Apparatus accordingto claim 3, wherein the energy means comprises a cylinder for the pistonto form a piston-cylinder combination; one of the cylinder parts of onepiston-cylinder combination is fixedly connected to the housing; thepistons of both said piston-cylinder combinations being connected to thebottom and top parts respectively; and the other cylinder part isslidably secured in the housing.
 7. Apparatus according to claim 6,including an additional cylinder-piston combination supporting the othercylinder part.
 8. Apparatus according to claim 7, wherein the housingcloses the top and bottom parts and has a separable, removable top andbottom cover; one of the cylinders being secured to the removable topcover, and the additional cylinder-piston combination being secured tothe bottom cover.
 9. Apparatus according to claim 8, wherein aT leastone of the top and bottom covers is removable from the housing as anentirety including the respectively connected piston-cylindercombination.
 10. Apparatus according to claim 1, wherein the meansapplying energy to the parts, and the means controlling the frequencyand amplitude parameter of application of energy comprises a source ofcontrol signals; transducer and amplifier means controlled by thecontrol signal; and means interconnecting the transducer means and theamplifier means with the energy means.
 11. Apparatus according to claim10, wherein the control signals derived from the source provide signalsof opposite polarity; and a pair of energy means are provided acting inopposite axial directions, one energy means each being controllable byone of the signals.
 12. Apparatus according to claim 1, includingresilient means supporting the housing.
 13. Apparatus according to claim1, wherein the housing is sealed; and suction outlet means are providedboth at the upper and lower portions of the housing.
 14. Compactionapparatus comprising a generally tubular shell (6); top piston andbottom pistons (12, 13) slidable in said shell, the material to becompacted being placed in the shell between the pistons; top and bottomhousing covers (7, 8) secured to the shell (6) and enclosing said topand bottom pistons, respectively; hydraulic power means (17, 22)controlling movement of the pistons into the shell to compact granulatetherein; an electro-hydraulic control loop (60, 65-85, 93-100); andprogram means (60) connected to said control loop and controlling thepower means (17, 22) applying hydraulic pressure by each said pistons(12, 13) with respect to at least one of: amplitude; frequency; and waveshape of applied power to provide for compacting and retracting movementof the pistons and vibratory impacts thereof to be transmitted from thepistons to the material within the shell, as controlled by said programmeans (60).
 15. Apparatus according to claim 14, wherein the programmeans controlling the power means comprises a random signal generatorproviding non-cyclically recurring power control signals.
 16. Apparatusaccording to claim 14, wherein the program means controlling the powermeans comprises a signal generator; and the electro- hydraulic controlloop comprises transducer means connected to the power means totransduce the signals from the signal generator to compression strokesby said top, and bottom piston, respectively.
 17. Apparatus according toclaim 16, wherein the signal controlling application of power to one ofthe pistons is a slowly, or unvarying compression signal and the signalcontrolling the other piston is a pulse-type signal providing impact, orblow-type excursions of the other piston at non-cyclically recurringrates.
 18. Apparatus according to claim 15, wherein the signal from thesignal generator controlling application of power controls both saidpistons to move synchronously in opposition towards each other toprovide counter-acting compression impacts against the material in theshell.
 19. Apparatus according to claim 2, comprising hydraulicconnection means connecting the fluid energy source and thecylinder-piston combination, the electrical signal controlled fluidcontrol means being interposed in the connection means and being locatedon the cylinder of the piston-cylinder combination.